Polarization entanglement and qubit error rate dependence on the exciton-phonon coupling in self-assembled quantum dots
Fuente:
arXiv
Enregistré dans:
| Auteurs principaux: | , , |
|---|---|
| Format: | Preprint |
| Publié: |
2025
|
| Sujets: | |
| Accès en ligne: | |
| Tags: |
Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
|
| _version_ | 1866908783851077632 |
|---|---|
| author | Dewan, Urmimala Kumar, Parvendra Sarma, Amarendra K. |
| author_facet | Dewan, Urmimala Kumar, Parvendra Sarma, Amarendra K. |
| contents | Polarization-entangled photons are key resources for a wide range of protocols in quantum computation and quantum key distribution. Achieving a near-unity degree of polarization entanglement is essential for minimizing qubit error rates in secure key distribution. In this work, we theoretically investigate polarization-entangled photon pairs generated via a quantum-dot radiative cascade embedded in a micropillar cavity. To account for the unavoidable exciton-phonon interactions in the quantum dot-cavity system, we develop a polaron master-equation framework and examine its impact on the degree of entanglement and the resulting qubit error rate. We derive analytical expressions for phonon-induced incoherent scattering rates and show that one-photon incoherent processes dominate, leading to a substantial reduction of entanglement. We further demonstrate that at elevated phonon-bath temperatures, cavity-mediated effects, such as cross-coupling between exciton states, ac Stark shifts, and multiphoton emission, are significantly suppressed due to phonon-induced renormalization of the cavity coupling strength and the Rabi frequency. Finally, we analyze a BBM92 quantum key distribution protocol and study the evolution of the qubit error rate as a function of the phonon-bath temperature. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2502_03413 |
| institution | arXiv |
| publishDate | 2025 |
| record_format | arxiv |
| spellingShingle | Polarization entanglement and qubit error rate dependence on the exciton-phonon coupling in self-assembled quantum dots Dewan, Urmimala Kumar, Parvendra Sarma, Amarendra K. Quantum Physics Optics Polarization-entangled photons are key resources for a wide range of protocols in quantum computation and quantum key distribution. Achieving a near-unity degree of polarization entanglement is essential for minimizing qubit error rates in secure key distribution. In this work, we theoretically investigate polarization-entangled photon pairs generated via a quantum-dot radiative cascade embedded in a micropillar cavity. To account for the unavoidable exciton-phonon interactions in the quantum dot-cavity system, we develop a polaron master-equation framework and examine its impact on the degree of entanglement and the resulting qubit error rate. We derive analytical expressions for phonon-induced incoherent scattering rates and show that one-photon incoherent processes dominate, leading to a substantial reduction of entanglement. We further demonstrate that at elevated phonon-bath temperatures, cavity-mediated effects, such as cross-coupling between exciton states, ac Stark shifts, and multiphoton emission, are significantly suppressed due to phonon-induced renormalization of the cavity coupling strength and the Rabi frequency. Finally, we analyze a BBM92 quantum key distribution protocol and study the evolution of the qubit error rate as a function of the phonon-bath temperature. |
| title | Polarization entanglement and qubit error rate dependence on the exciton-phonon coupling in self-assembled quantum dots |
| topic | Quantum Physics Optics |
| url | https://arxiv.org/abs/2502.03413 |